Development of a simple dry eye model in the albino rabbit and evaluation of some tear substitutes

The present paper is concerned with the development of a simple dry eye mod el in the rabbit, induced by daily repeated instillations of 1.0% atropine sulphate. The evolution of the dry eye syndrome in the animals was assessed by the Schirmer I test and by examination of the cornea after fluorescein staining. The model produced rapidly some typical dry eye symptoms and coul d be satisfactorily used for a preliminary assessment of the protective act ivity of some polymeric tear substitutes, These were based on hydroxypropyl methylcellulose, sodium hyaluronate, sodium polyacrylate or tamarind gum. T he latter polymer showed the best overall results. Ferning tests on the for mulations were also performed: their validity as predictors of the efficacy of tear substitutes is discussed.